Others well-versed in the field may dispute this and I would be eager to hear those objections, but I would posit Hanoi's War by Lien Hang-Nguyen as the best and preeminent account of Le Duan's involvement in North Vietnam's leadership during the war available for English-language audiences. As she writes, Le Duan was the first secretary/general secretary from 1960 until his death in 1986, which was the top leadership position in the Vietnamese communist party. Her research argues that by the mid-1960s, Le Duan was indeed the main architect behind policies both with regard to domestic North Vietnamese politics and the prosecution of the war. Ho Chi Minh, the "grandfather", Vladimir Lenin-esque figure for the Vietnamese independence movement, died in 1969 with his involvement in day-to-day policies greatly diminished by this point. Le Duan would remain the top policy-maker in Hanoi through the end of America's involvement in Vietnam and well into the 1980s.

To be clear, Le Duan was not an undisputed king. A central revelation from Nguyen's study is her profiling of the various factions that emerged, the key figures who had serious conflicts with one another, and the power struggles that occurred behind the curtain. But it was Le Duan who managed to quash opposition in the end and maximize his decision-making power through controlling the levers of the party, the military, and the police. (Nguyen's work also presents the fascinating argument that there was significant antiwar sentiment among both the public of North Vietnam and members of the military, NLF, and the government.)

Nguyen was one of the first to present this argument of Le Duan's importance to an English audience because of a number of important factors. She was the first scholar to be given access by the Vietnamese government to the archival records of the Ministry of Foreign Affairs. Her unique access to crucial Vietnamese records was compounded by connections and interviews with former North Vietnamese officials. While there have been other scholars fluent in Vietnamese and capable of lifting sources with a Vietnamese voice before, she was the first to present a comprehensive story of Vietnam's War from the North Vietnamese perspective as an outside scholar.

This information comes directly from having attending a talk by Nguyen where she relayed some of the background work that went into her book. This is my memory, so may be apocryphal or missing important details. From her account, Ken Burns' team did refer to her work often, although there were apparently disagreements about the ultimate portrayal of the North Vietnamese leadership. However, she was barely involved, and much of what she knew about how Ken Burns' team would use her work came second-hand. This would make sense with the argument in Burns' documentary about Le Duan, but also means that we cannot draw complete conclusions about sources which they used to form their framing in the documentary. Additionally, Nguyen's access to the archives was somewhat fortuitous, as she began her research in the late 90s which coincided with broader liberalization within Vietnam. Her own identity as the daughter of South Vietnamese refugees also enabled a level of, what I believe was, cultural and linguistic familiarity that opened doors for interviews that would have been otherwise difficult or impossible to get. She was the perfect person at the perfect time.